This is a thorny tree with pale green to red bark. The feathery foliage is similar to mimosa but has thorns at the base of each leaf. Clusters of bright yellow flowers are produced in the spring. This tree is the most important source of gum arabic, a natural polysaccharide that drips out of the cracks of the bark and hardens. The gum has many medicinal uses. It is reported that the tannin content of the bark and seeds can be up to 18%. Wood of this tree is reported to have been used in Ancient Egypt to make coffins and the Ark of the Covenant and some claim that it was used to build Noah's Ark.